The United States and the North Atlantic Treaty Organisation plan to nearly double the number of their rescue helicopters in Pakistan as United Nations officials report a ''desperate need'' for more aircraft in the aftermath of the October 8 earthquake.

At least 54,000 people were killed in the 7.6-magnitude earthquake, while severe weather conditions threatens 75,000 more who ''need urgent medical attention,'' NATO's Euro-Atlantic Disaster Response Coordination Center said in a situation report released in Washington October 26.

Many earthquake survivors were stranded in isolated mountain regions cut off by landslides and fallen rocks, accessible only by helicopter, mule or on foot, the Disaster Response Center reported.

Six United States Army CH-47 Chinook cargo helicopters are expected to arrive in Pakistan over the next several days, bringing the US helicopter fleet there to 18 aircraft.

Hundreds of American military personnel have deployed to Chaklala Air Base as part of a massive international relief effort. The American military contingent includes 233 members of a mobile army surgical hospital as well as a 32-member communication team.

NATO has also agreed to boost assistance to Pakistan by deploying more than 1,000 troops, including engineers, multinational medical units and water-purification teams.

It has airlifted 300 tonnes of emergency supplies from bases in Germany and Turkey.